The invention relates to concealed fire protection sprinklers having movable deflectors.
Fire protection sprinklers employ deflectors to spread out fire extinguishing fluid to cover a desired area. Some types of fire protection sprinklers employ movable deflectors that are in a retracted position when the sprinkler is inactive and in an extended position when the sprinkler is discharging fire extinguishing fluid.
Such movable deflectors are employed in concealed sprinklers that have covers that are installed flush with the ceiling mounting surface and which extend when the thermally responsive element of the sprinkler is exposed to a predetermined, elevated temperature. The deflector is in a retracted position above the lower surface of the ceiling when inactive and in a lowered position near or below the ceiling when active so as to spread the fluid out over a desired area in the room below, during a fire.
Anderson U.S. Pat. Nos. 4,014,388 and 4,066,129 describe concealed sprinklers with drop down deflectors that are supported by pins that slide within holes passing through arms of sprinkler frames, the pins extending upward into the space between the frame arms when in the inactive position. Leininger et al. U.S. Pat. No. 4,880,063 describes a concealed sprinkler with a drop down deflector that is supported by pins that slide within bosses that extend to the side of and are formed integrally on arms of a sprinkler frame.